CN100515927C - Method and apparatus for fluorine generation and recirculation - Google Patents

Method and apparatus for fluorine generation and recirculation Download PDF

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Publication number
CN100515927C
CN100515927C CNB2003801051373A CN200380105137A CN100515927C CN 100515927 C CN100515927 C CN 100515927C CN B2003801051373 A CNB2003801051373 A CN B2003801051373A CN 200380105137 A CN200380105137 A CN 200380105137A CN 100515927 C CN100515927 C CN 100515927C
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fluorine
equipment
separator
plasma generator
treatment chamber
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CN1720195A (en
Inventor
D·K·史密斯
M·M·贝森
W·M·霍尔比
S·F·霍尼
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MKS Instruments Inc
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MKS Instruments Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/08Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
    • B01J19/087Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy
    • B01J19/088Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor employing electric or magnetic energy giving rise to electric discharges
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00Halogens; Halogen acids
    • C01B7/19Fluorine; Hydrogen fluoride
    • C01B7/20Fluorine
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J19/00Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J19/08Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B03SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03CMAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
    • B03C3/00Separating dispersed particles from gases or vapour, e.g. air, by electrostatic effect
    • B03C3/34Constructional details or accessories or operation thereof
    • B03C3/36Controlling flow of gases or vapour
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/00049Controlling or regulating processes
    • B01J2219/00164Controlling or regulating processes controlling the flow
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2219/00Chemical, physical or physico-chemical processes in general; Their relevant apparatus
    • B01J2219/08Processes employing the direct application of electric or wave energy, or particle radiation; Apparatus therefor
    • B01J2219/0894Processes carried out in the presence of a plasma

Abstract

The invention relates to apparatus and methods for generating and recycling fluorine. The applicants recognized that a fluorine separator, used either alone or in combination with a plasma generator can produce sufficient quantities of fluorine at its point of use for thin film processing. The fluorine separator can take the form of a condenser, a membrane separation device, a fluorine ion conductor comprising a solid electrolyte, or a combination of the foregoing. In some embodiments, reaction products comprising fluorine are passed to the fluorine separator. In other embodiments, separated fluorine is passed, either alone or in conjunction with additional feed stock comprising fluorine, to a plasma generator. The fluorine separator allows fluorine to be recycled and waste products to be eliminated from the system.

Description

Produce the method and apparatus of fluorine and circulation fluorine
Technical field
The present invention relates to the generation and the circulation of fluorine, more specifically, relate to generation and circulation at the place to use fluorine.
Background technology
Fluorine is a high reactivity and highly toxic at its atom and molecular state.Fluorine is reluctant to use in most of laboratories, the expense of necessary safety equipment during owing to its danger and use.But some industry finds that fluorine can be than other known chemical product performance more important role.
Traditionally, molecular fluorine produces the electrolysis from HF.NF 3Also be used for producing fluorine, particularly in the processing film industry, as the manufacturing of semi-conductor and lithographic plate indicating meter always.Yet, HF and NF 3All be deleterious, and need the special disposal of high cost.
If fluorine can be produced from nontoxic and inert fluorochemicals, just can significantly reduce danger and with the relevant expense of use fluorine.For example, be used for the comb of such compound and system of distribution needn't according to HF or NF 3The comb and the relevant strict demand that distributes.The place to use is the closer to the production site of fluorine, and the danger of its use is more little.
And, if the by-product recovery fluorine that can produce when it uses then can more effectively use fluorine.The recovery of fluorine can make the total amount minimum of the required fluorine starting compound of specific end use.The recovery of fluorine also makes danger and carries relevant expense to reduce to minimum with fluorine.
Therefore, need produce fluorine safely in as close as possible its place to use; Need produce fluorine by avirulent inertia fluorochemicals; And by-product recovery fluorine that need be when it uses.
Summary of the invention
The applicant recognizes that the fluorine separator uses separately or combines with plasma generator, can produce the fluorine of q.s in the place that is used for processing film.The fluorine separator can be a condenser, and membrane separation unit comprises the fluorine ion conductor or the aforesaid array configuration of solid electrolyte.
The fluorine separator can be used for various fluoro-gas, as F 2, HF, SF 6, NF 3, CF 4, C 2F 6, C 3F 8With other fluorine cpd.In the various fluoro-gas, think for example CF 4, C 3F 8, C 2F 6And SF 6It is the inertia transmission medium of fluorine.And the fluorine separator when using separately or being used in combination with plasma generator makes the circulation of fluorine become possibility.
On the one hand, the present invention normally is used for the equipment of production atomic fluorine flux, it is characterized by casing, electrochemical cell and adapter.Casing has import, is used for accepting fluoro-gas.What electrochemical cell had at least one electrode and close this at least one electrode is the fluorine ion conductor of solid electrolyte.Electrochemical cell is from the fluoro-gas separate fluorine.Electrochemical cell to small part is contained in the casing and exit passageway is arranged.Take over and then connect exit passageway to treatment chamber.In the embodiment, this is taken over by plasma generator and connects exit passageway to treatment chamber.
In each embodiment in front, the form of electrochemical cell is a pipe or a plate.
In some embodiment in front, electrode comprises negative electrode, and electrochemical cell also comprises the anode near fluorine ion conductor.In these embodiments, anode is a film.But the feature porousness of this film or pattern, can make on the anode that to form molecular fluorine minimum.With respect to film thick conductive grid is set.In some embodiments, anode comprises nickel porous or stainless steel.
On the other hand, the present invention normally is used for producing the equipment of fluorine gas, it is characterized in that having individual plasma generator and fluorine separator.Plasma generator has import and the outlet that is used for accepting fluorine-containing raw material.Plasma generator forms plasma body, raw material can be decomposed into various reaction product.The fluorine separator has import and the fluorine outlet that is connected to plasma generator outlet, and import is used for the acceptable response product.The fluorine separator can be a membrane separation unit, and condenser is the fluorine ion conductor of solid electrolyte, or aforesaid combination.The fluorine separator separates fluorine with other reaction product.
In the embodiment of front equipment, various other parts or connection can be arranged, to reach various objectives.For example, equipment can comprise flow rate control device, directly or indirectly is connected to the fluorine outlet of fluorine separator.Similarly, the embodiment of present device can comprise second plasma generator, can directly or indirectly be connected to the fluorine outlet.The inlet of fluorine separator in some embodiments, is connected to the plasma generator outlet by treatment chamber.In the embodiment, the fluorine outlet is connected to the plasma generator outlet indirectly, thereby makes the fluorine gas circulation.For example, the fluorine outlet can be connected to the plasma generator inlet by a buffer space.
Another aspect, the present invention normally produces the equipment of the fluorine gas that uses at treatment chamber.Feature of the present invention is to be used for isolating from fluorine-containing raw material solid electrolyte, pressure control device and the adapter of fluorine.Solid electrolyte is a partially conductive, means to a certain degree conduction electron and ion, and has inlet face and the exit face (" conduction " is meant the medium of energy conduction electron as used herein) of accepting raw material.Pressure control device is near the inlet face of solid electrolyte.Pressure control device makes raw material be kept above fluorine dividing potential drop at exit face in the dividing potential drop of the inlet face of solid electrolyte.Take over directly or the exit face of solid electrolyte is connected to treatment chamber by plasma generator.
In similar one side, the invention provides the method that preparation is used for the atomic fluorine flux of treatment chamber.In this method, providing what have inlet face and exit face is the fluorine ion conductor of solid electrolyte.Accept fluorine-containing raw material at the fluorine ion conductor inlet face.Use fluorine ion conductor, fluorine is separated from the raw material that comprises fluorine.Fluorine is supplied with treatment chamber from the fluorine ion conductor exit face.
On the other hand, the present invention provides a kind of method that produces fluorine gas usually.With plasma body fluorine-containing raw material is decomposed into reaction product, and fluorine is separated with other reaction product with the fluorine separator.The fluorine separator can be a membrane separation unit, is the fluorine ion conductor of solid electrolyte, or condenser.
Another aspect, the present invention provides a kind of method of the fluorine gas that circulates usually.Accept waste gas from treatment chamber.With the fluorine ion conductor that is solid electrolyte fluorine is separated from fluoro-gas.Molecule or atomic fluorine are compressed, and make it circulation.
Each embodiment of previous methods also comprises one or more following steps: with plasma body molecular fluorine is decomposed into atomic fluorine; Provide atomic fluorine to treatment chamber; Or undesirable product separates with fluorine in the discharge separating step.In the embodiment, exhaust is the cleaning exhaust of treatment chamber.In another embodiment, can compress with fluorine ion conductor and/or pump.
In some embodiment in front, pressure-controlling is used for being suppressed at the fluorine combination again of fluorine separator outlet.For example, in so a kind of equipment, pressure control device suppresses the again combination of fluorine at exit face.Pressure control device can comprise pump.The pressure of fluorine separator outlet face can keep or be lower than 100 torrs, or keeps or or be lower than 20 torrs.
Similarly, in some embodiment in front, temperature control is used to suppress the again combination of fluorine at fluorine separator outlet face.For example, in so a kind of equipment, temperature-control device is controlled at least one surperficial temperature.This surface can be the surface of electrolytical surface or fluorine exit passageway.
By following explanation and claims, aforementioned aspect of the present invention and other aspects, feature and advantage will be conspicuous.
The accompanying drawing summary
In the accompanying drawing, similarly numeral refers generally to the same parts in all figure.Parts in the accompanying drawing are also not necessarily proportional, and emphasis generally just illustrates principle of the present invention.In the explanation, will various embodiment of the present invention be described below referring to following accompanying drawing, in the accompanying drawing:
Shown in Figure 1 is equipment according to the generation fluorine gas of one embodiment of the present invention;
Shown in Figure 2 is equipment according to the generation fluorine gas of another embodiment of the present invention;
Shown in Figure 3 is electrochemical cell synoptic diagram according to one embodiment of the present invention;
Fig. 4 A, 4B, 4C, 4D and 4E are the different figure according to the fluorine separator of the electrochemical cell of Fig. 3;
Shown in Figure 5 is the equipment with generation fluorine gas of fluorine separator of the present invention;
Shown in Figure 6 is equipment according to generation of the present invention and circulation fluorine gas.
Explanation
Referring to Fig. 1, the equipment 100 according to the generation fluorine gas of one embodiment of the present invention is characterized in that plasma generator 130 and fluorine separator 160.Plasma generator 130 in different embodiments, is a microwave plasma-generator, RF inductively coupled plasma producer, RF annular inductively coupled plasma producer, or RF capacitance coupling plasma producer.Plasma generator 130 can be, for example, and ASTRON TMOr Rapid TmThe reactant gas producer.Plasma generator 130 comprises import 132 and outlet 134.Fluorine-containing raw material is accepted in import 132 at plasma generator 130.Plasma generator 130 forms plasma body, and plasma body resolves into each reaction product with raw material.Reaction product is discharged from plasma generator 130 by outlet 134.In different embodiments, plasma generator 130 is at normal atmosphere or be lower than under the normal atmosphere and operate.
Among Fig. 1, fluorine separator 160 is condensers, and partial reaction product at least cools off and condense.Condenser 160 comprises import 162 and fluorine outlet 164.The import 162 of condenser 160 is connected to the outlet 134 of plasma generator.Condenser 160 is by import 162 acceptable response products.In the embodiment, condenser 160 also comprises the outlet (not shown) of unwanted product, and unwanted product is by this outlet eductor condenser.In another embodiment, unwanted product is discharged from fluorine by plasma generator and waste outlet 136.
In different application, raw material is one or more fluoro-gas, as F 2, HF, SF 6, NF 3, CF 4, C 2F 6, C 3F 8With other fluorine cpd.Not necessarily circulation, and be called raw material with fresh gas supplied.In the fluoro-gas, think, for example CF 4, C 2F 6, C 3F 8And SF 6It is the inertia transmission medium of fluorine.In various application, reaction product comprises sulphur and carbon compound.Raw material is SF 6The time, reaction product can comprise the F of gas phase and liquid form 2, S XF yAnd S.
In the various application, except that fluorine-containing raw material, also have a kind of reactant gases to feed plasma generator 130.During these were used, plasma generator 130 formed plasma body, and this plasma body decomposes or excites this reactant gas, and fluorine-containing raw material.Reactant gas feeds plasma generator 130 by import 132.Reactant gas was O during some was used 2Fluorine can produce unwanted S with separating of reaction product 2And/or SO 2
In an embodiment of equipment 100, condenser 160 separates and output F 2, have second a plasma generator (not shown) to form plasma body, with F 2Be decomposed into atomic fluorine.The atomic fluorine that this embodiment forms can feed treatment chamber.
In some embodiment of equipment 100, there is individual mass flow control device (not shown) to regulate the flow of fluorine by outlet 164.The mass flow control device can directly or indirectly be connected to fluorine outlet 164.The mass flow control device can be a pressure control device, only comprises a pressure control device or be independent of pressure only regulating flow.This device can be used to control the pressure that fluorine exports 164 places.
In some embodiment of equipment 100, condenser 160 imports 162 are connected to plasma generator outlet 134 by a treatment chamber (not shown).This arrangement makes the reaction product separate fluorine of condenser 160 from treatment chamber.When fluorine outlet 164 was also connected to the import 132 of plasma generator 130 by pump or other compression sets, equipment 100 just made fluorine gas circulate.In such embodiment, fluorine outlet 164 is connected to the import 132 of plasma generator 130 by the buffer space (not shown).The closed volume that some suitable control valves and inductor block are arranged in this buffer space comprises.Buffer space can store a certain amount of fluorine, and making to have a delay before reusing fluorine.
The feature that produces the method for fluorine gas is with plasma body fluorine-containing raw material to be decomposed into reaction product, and with the fluorine separator fluorine to be separated with other reaction product.This method has been utilized Fig. 1 equipment 100 or has been had the advantage of one group of parts of similar effect.For example, although the feature of the equipment of Fig. 1 100 is condensers 160 fluorine is separated with other reaction product, this method not necessarily needs condenser.This method can be used membrane separation unit, is the fluorine ion conductor of solid electrolyte, and condenser, or aforesaid combination are finished separation.
Referring to Fig. 2, the equipment 200 according to the generation fluorine gas of another embodiment of the present invention is characterized in that having individual plasma generator 230, the first fluorine separators 260 and the second fluorine separator 280.Plasma generator 230 comprises import 232 and outlet 234, and its 26S Proteasome Structure and Function is similar to the described plasma generator 130 of Fig. 1.Equally, the first fluorine separator 260 is condensers, comprises import 262 and outlet 264, and 26S Proteasome Structure and Function is similar to the described condenser 160 of Fig. 1.This condenser 160 also can be used to cool off the gas that enters before second separator 280.
In embodiment shown in Figure 2, the second fluorine separator 280 is membrane separation units.Membrane separation unit 280 comprises inlet face 282 and exit face 284.The inlet face 282 of membrane separation unit 280 is connected to the outlet 264 of condenser 260.In the embodiment like this, membrane separation unit 280 is used for being connected with condenser 260, because condenser 260 separate fluorine and reaction product completely effectively.The atomic fluorine that is produced by the plasma decomposes of plasma generator 230 can be combined into molecular fluorine again before entering membrane separation unit 280.Therefore, membrane separation unit 280 is used for isolated molecule fluorine and reaction product.
In the embodiment of Fig. 2, membrane separation unit 280 features are to allow particle diameter approximately
Figure C20038010513700081
Particle by but significantly greater than
Figure C20038010513700082
Particle do not pass through.The diameter of molecular fluorine approximately
Figure C20038010513700083
Be in a ratio of less with most of possible degradation productions.For example, SF 6Diameter approximately
Figure C20038010513700084
And O 2Diameter approximately
Figure C20038010513700085
In another embodiment, the feature of membrane separation unit 280 is porousness or the passage that suitable feature is arranged.In some such embodiments, the temperature of controlling diaphragm is set up the perviousness that needs for film.In the embodiment of Fig. 2, add be or displaced be between the inlet face 282 of membrane separation unit 280 and exit face, to adopt the fluorine partial pressure gradient, to quicken sepn process.
At Carbon Membrane Separator for Elimination of SF 6Among the Emissions FromGas-Insulated Electrical Utilities (with reference to be incorporated into this), from Carbon Membranes, Ltd.ofArava, the Dagan of Israel etc. have described the preparation of Carbon Molecular Sieve Membrane and from SF 6Separate O 2And N 2Application.Adopt similar method to prepare molecular screen membrane, can separate F 2With other may be bigger molecule and particle.
The general feature of the equipment 200 of Fig. 2 is and a kind of variant to Fig. 1 equipment 100 described embodiments and application.In addition, in another embodiment that produces fluorine gas equipment, membrane separation unit 280 as described in regard to Fig. 2, has substituted the just described condenser 160 of Fig. 1.In another embodiment, equipment 200 comprises condenser 260, but does not have membrane separation unit 280.
Shown in Figure 3 is to join to be used for isolating from fluoro-gas the synoptic diagram of the electrochemical cell 300 of fluorine in the embodiment of the present invention.The feature of Fig. 3 is that individual electrode (330 or 370) and fluorine ion conductor 350 are arranged, and comprises the solid electrolyte near this electrode.In some embodiments, solid electrolyte comprises Pb 2Sn 2F 4In some embodiments, solid electrolyte is that portions of electronics conducts electricity, the electron conduction that has diffusion or distribute.This electrode can be formed by any suitable electrode materials known in the art.In different embodiments, electrochemical cell 300 is tubular, plate shape, or dish type.
In some embodiments, the feature of electrochemical cell 300 is second electrodes that a power supply 380 of separating and close solid electrolyte 350 are arranged.Power supply 380 is energized to two electrodes, thereby makes an electrode as negative electrode 330, and another is as anode 370.
In some embodiments, the anode 370 of Fig. 3 is films.To the object of the invention, if fluorion and/or atom are passed through, anonite membrane is very thin.In such embodiment, anode material comprises nickel porous or Porous Stainless Steel.In each embodiment, the feature of film is porousness or the pattern with the many openings that separate, and makes near the minimum fluorine of formation anode 370.In some embodiments, anode 370 features are thick conductive grid.This grid has improved heat dissipation and has reduced power loss.In some such embodiments, remove the some parts of part single monolayer thick conductive layer on solid electrolyte, form anode 370, it comprises film and thick conductive grid.In other embodiments, film and conductive grid form layer separately.
In another embodiment, electrochemical cell 300 or comprise the device that applies electric field to solid electrolyte 350 surfaces.Thereby directly from solid electrolyte 350 surface extraction fluorions.In a similar embodiment, the thin doped layer of solid electrolyte 350 is as anode 370, and electrode is as negative electrode.
In operation, the solid electrolyte 350 of electrochemical cell 300 is isolated fluorine from fluoro-gas.Near negative electrode 330, fluorine is ionized, and produces two negative ions.Fluorion is then by 370 migrations of solid electrolyte 350 anode.Effect of electric field on the solid electrolyte 350 can be quickened this migration.For example, power supply 380 can produce electric field on solid electrolyte 350, quicken this migration.Add or alternate is that the cathode plane 310 of fluorine ion conductor 350 and the fluorine partial pressure gradient between the anode surface 390 can be quickened this migration.
During great majority were used, fluorion provided its electronics to anode 370, combined with another fluorine atom then again and formed molecular fluorine.In these were used, electrochemical cell 300 can be used to isolate molecular fluorine from fluoro-gas, and molecular fluorine is compressed to required pressure.Electrochemical cell 300 is sent to high pressure on its anode surface 390 with the low-pressure gas of cathode side 310 with electrochemical means.In this mode, use electrochemical cell 300 to cancel to be used for the needs of another mass flow control device that compresses molecular fluorine.
In some applications, the pressure and/or the temperature of the anode side 390 of control ionophore 350 are to suppress the formation of molecular fluorine.Under suitable low pressure and/or high temperature, fluorine atom can be separated and no longer combination.Under low pressure reduced by two possibilities that fluorine atom combines, and be shortened in the atom time of tiding over of taking place probably again on the bonded material surface under the high temperature.In some such application, keep or be lower than 100 torrs at the pressure of the anode side 390 of ionophore 350.In related application, the pressure of the anode side 390 of ionophore 350 keeps or is lower than 20 torrs.
The difference of the fluorine dividing potential drop between two electrodes of electrochemical cell produces possible difference, make ion from the high partial pressures side to low dividing potential drop side.Under the situation, can provide circuit like this, carry the electronics that passes electrochemical cell thereby return by negative fluorion from anode to negative electrode.This return circuit can be electrochemical cell outside (as passing through electric wire).Perhaps, this circuit can return by electrochemical cell, if form certain electron conduction in ionogen or cell structure.
Fig. 4 A, 4B, 4C, 4D and 4E are the different views according to the fluorine separator 400 of one embodiment of the present invention.It shown in Fig. 4 A the 3-D view of the casing 415 of fluorine separator 400.Casing 415 in Fig. 4 A embodiment comprises the import 410 of accepting fluoro-gas, the outlet of fluorine outlet 420 and unwanted product (not shown, but be positioned at the reverse side of import 410).Be the identical 3-D view with the fluorine separator 400 of Fig. 4 A shown in Fig. 4 B, but removed its casing 415, disclose its internal structure.Some plates 430 are mechanically connected to supporting side walls 440, form parts in the casing 415.Each plate 430 comprises a plurality of layers.Fig. 4 C is the vertical view of the casing 415 explanation I-I ' positions of fluorine separator 400.Fig. 4 D is the sectional view of fluorine separator 400 in the internal structure of I-I ' position.It shown in Fig. 4 D the sectional view of the plate 430 identical with Fig. 4 B.Show the mechanical connection of plate 430 and supporting side walls 440 once more.
Fig. 4 E be fluorine separator 40 internal structures veneer 430 than detailed cross sectional view.Shown in Fig. 4 E, fluorine separator 400 shown in Figure 4 comprises a plurality of electrochemical cells shown in Figure 3 300.Each electrochemical cell 300 is placed in the casing 415.Each electrochemical cell comprises outer electrode 432, solid electrolyte 434, interior electrode 436 on metal fixing 438 and heat setting spare 439.Electrode 432 and 436 all allows fluorion to pass through.Have in metal fixing 438 and the heat setting spare 439 be connected to electrochemical cell 300 imbed gas passage 426.Respectively imbed gas passage 426 and be also connected to central gas 424 in structure unit 439, this structure unit 439 is supporting plate 430.Central gas 424 in each plate 430 is connected to the central gas 422 in sidewall 422, and this passage is delivered to fluorine outlet 420 with fluorine.Shown in Fig. 4 E embodiment, each plate 430 can have electrochemical cell at its top surface and basal surface.
In the operation, fluoro-gas is accepted in the import 410 of fluorine separator 400.Electrochemical cell in this gas and the casing 415 interacts.Fluorine comes out from this gas delivery, and be transferred to by electrochemical cell and imbed gas passage 426, the central gas 424 to the plate, the central gas 422 to the sidewall 440 is then to fluorine outlet 420.Fluorine is discharged from fluorine separator 400 by fluorine outlet 420.Usually, fluorine separator 400 produces molecular fluorine air-flow 420 in fluorine outlet 420.But as reference Fig. 3 explanation, the condition on the anode of anodic feature and electrochemical cell can suppress the formation of molecular fluorine, thereby forms atomic fluorine flux in fluorine outlet 420.The isolating by product of fluorine is discharged from the outer case of fluorine separator 400 by waste product outlet (not shown).
The feature of each embodiment that comprises the fluorine separator of solid electrolyte is that individual temperature-control device is arranged, and has controlled at least one surperficial temperature.The temperature-control device of fluorine separator 400 for example, can be a heat setting spare 439.Heat setting spare 439 may command solid electrolytes 434 are imbedded gas passage 426, and/or the surface temperature of the interior central gas 424 of plate.In other embodiments, temperature-control device is active or passive.Temperature control is to suppressing the usefulness that is formed with of molecular fluorine.Temperature control can also be optimized electrolytical ionic conductivity.
In the embodiment of an application, there is an adapter (not shown) will export 420 near fluorine outlet 420 and is connected to treatment chamber.For example adapter can be accepted a pipe and be connected to treatment chamber.The fluorine that operation fluorine separator 400 produces just can be imported treatment chamber.In an application, be directly used in processing film from fluorine separator 400 isolating fluorine atom air-flows, as chamber cleaning or product etching.Perhaps, import treatment chamber by plasma generator, this plasma body producer molecular fluorine is decomposed into atomic fluorine from the molecular fluorine of fluorine separator.Fluorine flux from fluorine separator 400 can also be used for other application.These application comprise the production of fluoridizing of plastics and fluoride gas and material.
Fluorine separator 400 can be used in the equipment of Fig. 1, instead of condensor 160.Similarly, fluorine separator 400 also can be used for the equipment of Fig. 2, as the second fluorine separator 280.Fluorine separator 400 can also replace fluorine separator 280 and plasma generator 230.This embodiment is to can be directly useful at raw material and reactant gases that the fluorine ion conductor on the suction side decomposes by electrochemical cell.
Shown in Figure 5 is generation fluorine gas equipment 500 according to one embodiment of the present invention.This equipment can comprise available plasma generator 520 and fluorine separator 540.The outlet 526 that plasma generator 520 has import 523 that fluorine-containing raw material uses and reaction product to use.The structure of plasma generator 520 and effect are similar to the just described plasma generator 130 of Fig. 1.
Fluorine separator 540 has import 544 and fluorine outlet 543, and import 544 is connected to the outlet 526 of plasma generator 520, in order to the acceptable response product.In each embodiment, the structure of fluorine separator 540 and effect are similar to the just described condenser 160 of Fig. 1, with regard to described condenser 260 of Fig. 2 or membrane separation unit 280, or with regard to the described electrochemical cell 300 of Fig. 3.In the embodiment, the structure of fluorine separator 540 and effect are similar to the just described fluorine separator 400 of Fig. 4.
In the operation, fluorine-containing raw material such as SF 6Or CF 4 Feed plasma generator 520 by import 523.In some applications, a kind of reactant gas can also feed plasma generator 520 by import 523.Plasma generator becomes reaction product with any reactant gas of fluorine-containing raw material of the plasma decomposes of its generation and existence.Reaction product can comprise molecular fluorine, atomic fluorine, carbon compound, SF 6, SF 4, S and SO 2, also have other products.Reaction product is discharged from plasma generator 520 by outlet 526, feeds fluorine separator 540 by import 544.Fluorine separator 540 separate fluorine and other reaction product allow fluorine by fluorine outlet 543.In Fig. 5 embodiment, fluorine separator 540 does not need the outlet 546 of product in addition, allows unwanted product by this outlet.
Fluorine separator 540 at Fig. 5 produces in the embodiment of atomic fluorine flux, and further the fluorine decomposition is not essential, can be by pipeline and gas distribution component such as spray header feeding treatment chamber 590 from the fluorine of fluorine separator 540.Atomic fluorine can be used in the treatment chamber 590, for example, is used for making the treatment chamber cleaning.
Fluorine separator 540 at Fig. 5 produces in the embodiment of molecular fluorine air-flows, and further to decompose may be essential to fluorine, arrives treatment chamber 590 to guarantee fluorine with its effective form.In these embodiments, can in equipment 500, add second plasma generator 580.The structure of second plasma generator 580 and effect also are similar to the just described plasma generator 130 of Fig. 1.
In such embodiment, molecular fluorine feeds second plasma generator 580 by import 563.Its plasma body of second plasma generator, 580 usefulness is decomposed into atomic fluorine with molecular fluorine.Because the activity of atomic fluorine is preferably with the close treatment chamber 590 that is connected to of the outlet of second plasma generator 580.In the embodiment, for example, second plasma generator 580 is directly connected to treatment chamber 590.In another embodiment, for example, the distance that second plasma generator 580 and treatment chamber are 590 is as far as possible little.In the 3rd embodiment, relate to being arranged as of equipment of fluid flow, second plasma generator 580 is devices of the most close treatment chamber 590.
Fig. 6 is the synoptic diagram according to the equipment 600 of embodiment of the present invention generation and circulation fluorine gas.This equipment 600 comprises plasma generator 620, fluorine separator 660, and the device 610 of feeding fluorine compound feedstock is with the device 670 of waste material discharge and the pipe connecting of a plurality of circulation fluorine gas.In the embodiment shown in Figure 6, equipment 600 is used for being created in the fluorine that uses in the treatment chamber 640, and from the treatment chamber relief outlet fluorine is circulated.
Plasma generator 620 in the equipment 600 has import 622, and fluorine compound feedstock feeds by this import.The structure of plasma generator 620 and effect are similar to the just described plasma generator 130 of Fig. 1, and raw material is resolved into degradation production.Plasma generator 620 also is useful on the outlet 624 of degradation production.As shown in Figure 6, fluorine compound feedstock needn't be at import 622 feeding equipment 600.
Fluorine separator 660 in the equipment 600 has import 662 and fluorine outlet 664.As shown in Figure 6, import 662 can be connected to the outlet 624 of plasma generator 620 by treatment chamber 640.In other embodiments, use the device of fluorine and plasma generator 620 to exchange.Fluorine separator 660 is with fluorine other separation of by-products when using fluorine.In some embodiments, as shown in Figure 6, fluorine separator 660 also has a waste product outlet 666, the isolating by product slave unit 600 of fluorine can be discharged.In other embodiments, equipment 600 comprises a similarly outlet, near fluorine separator 660 or at another correct position.
In different embodiments, the similar just described condenser 160 of Fig. 1 of the structure of fluorine separator 660 and effect, to described condenser 260 of Fig. 2 or membrane separation unit 280, or with regard to the described electrochemical cell 300 of Fig. 3.In embodiment shown in Figure 6, fluorine separator 660 comprises that just Fig. 3 is described is the conduit arrangements of a plurality of electrochemical cells.In the embodiment, the structure of fluorine separator 660 and effect are similar to the just described fluorine separator 400 of Fig. 4.
As shown in Figure 6, equipment 600 is included in the pipe connecting between the import 622 of the fluorine outlet 664 of fluorine separator 660 and plasma generator 620.The fluorine that this pipe connecting produces fluorine separator 660 is recycled.This pipe connecting comprises a buffer space 680 in some embodiments.
Building up fluorine in the buffer space, fluorine can be used from isolating flow of chamber relief outlet and time to be different from it.In the embodiment of Fig. 6, the fluorine that fluorine separator 660 produces mixes at meet 615 with fluorine-containing raw material, arrives the import 622 of plasma generator 620 afterwards.The other gas that uses in the equipment 600 also can feed in the import 622 of meet 615 or plasma generator 620 as reactant gas.
In order to circulate, accept to discharge gas from treatment chamber, isolate fluorine with comprising electrolytical fluorine separator from fluoro-gas, this molecular fluorine is compressed, and carries out working cycle.In addition, in equipment shown in Figure 6 600 operations, accept fluorine-containing raw material.But also acceptable response thing gas.Plasma generator 620 usefulness plasma bodys are decomposed into the various product atomic fluorine that comprise with fluorine-containing raw material.Atomic fluorine input treatment chamber 640.In one embodiment, treatment chamber 640 uses atomic fluorine to clean, and produces waste gas.Fluorine separator 660 separates fluorine with waste gas.This fluorine then is recycled to plasma generator 620, and for re-using, unwanted product is that (being part at least) lacks fluorine simultaneously, and slave unit 600 is discharged.Other embodiments can use a plurality of fluorine separators in treatment chamber 640 back.
Those skilled in the art can change embodiment described herein not departing under the described scope and spirit of the present invention of claims, revises and other enforcements.Therefore, the present invention is not subjected to previously described restriction, but is subjected to the restriction of the spirit and scope of following claims.

Claims (25)

1. equipment for preparing the atomic fluorine flux that treatment chamber uses, this equipment comprises:
Casing has the import of accepting fluoro-gas;
Be used for isolating from fluoro-gas the electrochemical cell of fluorine, electrochemical cell to small part is arranged in the casing, and exit passageway is arranged;
Described exit passageway is connected to the adapter of treatment chamber;
Described electrochemical cell comprises:
At least one electrode;
Near this electrode at least is the fluorine ion conductor of solid electrolyte.
2. equipment as claimed in claim 1 is characterized in that, the form of electrochemical cell is a pipe.
3. equipment as claimed in claim 1 is characterized in that, the form of electrochemical cell is a plate.
4. equipment as claimed in claim 1 is characterized in that described solid electrolyte has a surface, and this equipment also is included in the device that the solid electrolyte surface applies electric field, in order to directly from this surface extraction fluorion.
5. equipment as claimed in claim 1 is characterized in that each electrode is a negative electrode, and described equipment also comprises the anode near fluorine ion conductor.
6. equipment as claimed in claim 5 is characterized in that anode is a film.
7. equipment as claimed in claim 6 is characterized in that the characteristics of film are porous, can make the formation amount minimum of molecular fluorine on the anode.
8. equipment as claimed in claim 6 is characterized in that, the characteristics of film are that pattern is arranged, and makes the formation amount minimum of molecular fluorine on the anode.
9. equipment as claimed in claim 6 is characterized in that, anode is a thick conductive grid with respect to the film placement.
10. equipment as claimed in claim 6 is characterized in that anode comprises nickel porous.
11. equipment as claimed in claim 6 is characterized in that anode comprises Porous Stainless Steel.
12. equipment as claimed in claim 1 also comprises pressure control device, in order to suppress fluorine in exit passageway combination again.
13. equipment as claimed in claim 12 is characterized in that pressure control device comprises vacuum pump, exit passageway pressure is remained on or is lower than 100 torrs.
14. equipment as claimed in claim 13 is characterized in that pressure control device comprises vacuum pump, exit passageway pressure is remained on or is lower than 20 torrs.
15. equipment as claimed in claim 1 also comprises temperature-control device, controls at least one surperficial temperature of at least one ionogen and exit passageway.
16. equipment as claimed in claim 1 is characterized in that, described adapter is connected to treatment chamber by plasma generator with exit passageway.
17. a method for preparing the atomic fluorine flux of treatment chamber use, this method comprises:
The fluorine ion conductor that comprises solid electrolyte is provided, and this conductor has inlet face and exit face;
Accept fluorine-containing raw material at inlet face;
Isolate fluorine with fluorine ion conductor from fluorine-containing raw material;
Provide fluorine from exit face to treatment chamber.
18. method as claimed in claim 17 also is included in and applies electric field on the fluorine ion conductor, and fluorion is moved to exit face from inlet face.
19. method as claimed in claim 17 also comprises and improves the dividing potential drop of fluorine-containing raw material at the fluorine ion conductor inlet face, thereby fluorion is moved to exit face from inlet face.
20. method as claimed in claim 17 also comprises the temperature of controlling fluorine ion conductor, and fluorion is moved to exit face from inlet face.
21. method as claimed in claim 17 is characterized in that, fluorine-containing raw material comprises one or more and is selected from following material: F 2, HF, SF 6, NF 3, CF 4, C 2F 6, C 3F 8With other fluorine cpd.
22. method as claimed in claim 17, it is characterized in that, separating step comprises with fluorine ion conductor isolates molecular fluorine from fluorine-containing raw material, described method also comprises with the plasma decomposes molecular fluorine and produces atomic fluorine, describedly provides step to comprise atomic fluorine is supplied with treatment chamber by plasma generator from the exit.
23. method as claimed in claim 17 also comprises the pressure of controlling the exit, thereby inhibition fluorion and/or fluorine atom are in conjunction with forming molecular fluorine.
24. method as claimed in claim 23 is characterized in that, described controlled step also comprises and outlet pressure remained on or is lower than 100 torrs, to suppress fluorion and/or fluorine atom in conjunction with forming molecular fluorine.
25. method as claimed in claim 24 is characterized in that, described controlled step also comprises and outlet pressure remained on or is lower than 20 torrs, to suppress fluorion and/or fluorine atom in conjunction with forming molecular fluorine.
CNB2003801051373A 2002-12-06 2003-12-04 Method and apparatus for fluorine generation and recirculation Expired - Lifetime CN100515927C (en)

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US7238266B2 (en) 2007-07-03
JP2006508799A (en) 2006-03-16
KR20050092697A (en) 2005-09-22
WO2004053198A2 (en) 2004-06-24
WO2004053198A3 (en) 2005-03-31
CN1720195A (en) 2006-01-11
KR100994298B1 (en) 2010-11-12
AU2003298946A1 (en) 2004-06-30
DE60316020T2 (en) 2008-05-21
US20040109817A1 (en) 2004-06-10
AU2003298946A8 (en) 2004-06-30

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